Cooling System

The R6950 Twin Frozr III 1GD5 Power Edition/OC features MSI’s original cooler which consists of a copper base, five copper heat pipes, slim aluminum fins, fans, and an aluminum casing.

The heat pipes (the three in the middle are 6 millimeters in diameter whereas the two outermost ones are 8 millimeters) are soldered to the base as well as to the heatsink fins. They are all nickel-plated.

They are fitted into the grooves in the base. The copper base is about 3 millimeters thick at its slimmest point.

The power components and memory chips are cooled with an aluminum plate with thermal pads.

The fans are 74 millimeters in diameter. Their blades are shaped in a curious way:

MSI claims this design of the 13-blade impeller helps increase the air flow by 20%. The Twin Frozr III cooler is expected to be 11°C more efficient than the reference cooler while being quieter by 13.9 dBA.

The speed of the fans is PWM-regulated within a range of 1500 to 4600 RPM. They are manufactured by PowerLogic (the PLD08010S12HH model).

Each fan is specified to have a peak power draw of 4.2 watts (it is 4.45 watts according to our measurements). They seem to run on sleeve bearings which claim to have an extended service life.

We checked out the card’s temperature while running Aliens vs. Predator (2010) in five cycles at the highest settings (1920x1080, 16x anisotropic filtering and 4x full-screen antialiasing). We used MSI Afterburner 2.2.0 Beta 7 and GPU-Z 0.5.5 as monitoring tools. This test was carried out with a closed system case (you can view its full configuration in the appropriate section of the review) at an ambient temperature of 24°C. We had dismantled the card before the tests and replaced its default GPU thermal grease with Arctic MX-4.

Let’s see how efficient the cooler is in its two modes (Performance and Silent):

Performance mode

Silent mode

The GPU temperature reached 71°C in the Performance mode while the speed of the fans grew from 1840 to 3060 RPM. Interestingly, the temperature was a mere 1°C higher in the Silence mode but the speed range was at a much quieter level (1560 to 2700 RPM) even though not exactly silent. So, we tried to set the cooler’s speed at 1920 RPM (43% from the maximum) and it coped with its job, keeping the GPU temperature no higher than 77°C.

1920 RPM

The temperature was only 61°C at the maximum speed of the fans.

4580 RPM

The card is of course very loud at its max fan speed. How loud, exactly?

We measured the level of noise using an electronic noise-level meter CENTER-321 in a closed room about 20 sq. meters large. The noise-level meter was set on a tripod at a distance of 15 centimeters from the graphics card which was installed on an open testbed. The mainboard with the graphics card was placed at an edge of a desk on a foam-rubber tray.

The bottom limit of our noise-level meter is 29.8 dBA whereas the subjectively comfortable (not low, but comfortable) level of noise when measured from that distance is about 36 dBA. The speed of the graphics card’s fans was being adjusted by means of a controller that changed the supply voltage in steps of 0.5 V.

For the comparison’s sake, we’ve added the results of the Sapphire Radeon HD 6950 Toxic Edition into the next diagram:

The R6950 Twin Frozr III 1GD5 Power Edition/OC is clearly quieter than the Sapphire card which in its turn is quieter than the reference Radeon HD 6970. However, even the MSI card can’t be called really quiet. It is such in 2D applications when its fans have a speed of 1550 RPM and lower (Silent mode) but when the fans accelerate to 1950 RPM and higher, the Twin Frozr III cooler becomes rather uncomfortable. So, we don’t think that the MSI card will suit those users who want a silent computer.